diverticulitis (acute)

Last edited 03/2021 and last reviewed 07/2021

Diverticulosis is a digestive condition characterised by small pouches (diverticula) that protrude from the walls of the large intestine.

Acute diverticulitis is a condition which results from acute inflammation of one or more diverticula.

This condition has a higher incidence in females than males and is most often seen in the 50-70 year old age group.

The true prevalence of diverticulosis is difficult to determine because most patients are asymptomatic. It is age dependent and relatively uncommon in people aged under 40, although in recent years there has been a dramatic rise in the prevalence in this age group. In people aged over 65 the prevalence is up to 65%.


About 80 to 85% of people affected by diverticulosis remain asymptomatic, and 10 to 15% develop symptomatic diverticular disease including acute diverticulitis and its complications (perforation, abscess formation, haemorrhage, fistula and obstruction).

Symptoms and signs of acute diverticulitis

Suspect acute diverticulitis if a person presents with constant abdominal pain, usually severe and localising in the left lower quadrant, with any of the
following:

  • fever or
  • sudden change in bowel habit and significant rectal bleeding or passage of mucus from the rectum or
  • tenderness in the left lower quadrant, a palpable abdominal mass or distention on abdominal examination, with a previous history of diverticulosis or diverticulitis
  • Be aware that in a minority of people and in people of Asian origin, pain and tenderness may be localised in the right lower quadrant

Symptoms and signs of complicated acute diverticulitis


Suspect complicated acute diverticulitis and refer for same-day hospital assessment if the person has uncontrolled abdominal pain and any of the
features in table below.

Symptom or sign Possible Complication
Abdominal mass on examination or peri-rectal fullness on digital rectal examination Intra-abdominal
abscess
Abdominal rigidity and guarding on examination Bowel perforation
and peritonitis
Altered mental state, raised respiratory rate, low systolic blood pressure, raised heart rate, low tympanic temperature, no urine output or skin
discolouration
Sepsis
Faecaluria, pneumaturia, pyuria or the passage of faeces through the vagina Fistula into the
bladder or vagina
Colicky abdominal pain, absolute constipation (passage of no flatus or stool), vomiting or abdominal distention Intestinal obstruction

Notes (2):

  • imaging is necessary to make an initial diagnosis of diverticulitis and determine disease severity
    • colonoscopy should be done six to eight weeks after diagnosis to rule out a missed colon malignancy
  • antibiotic treatment is used selectively in immunocompetent patients with mild acute uncomplicated diverticulitis
  • prevention of diverticulitis
    • a high quality diet, physical activity, not smoking, and a normal body mass index are associated with a reduced risk of diverticulitis
    • avoid regular use of non-steroidal antiinflammatory drugs
    • do not need to avoid nut, corn, and popcorn consumption
    • 5-aminosalicylic acid, probiotics, and rifaximin should not be used to prevent recurrent diverticulitis
    • decision to undergo prophylactic colon resection should be individualized to consider severity of diverticulitis, general health and immune status, patient's preferences and values, and benefits and risks

Reference: